OMS Black Slipstream Monoprene Fins Size M A12318004 The legendary OMS SlipStream Monoprene Fins, made from neutral buoyancy Black Monoprene ? Elastomer Material are so light and very powerful, there is no surprise that they have become renowned amongst the most meticulous Technical Divers as ?The Fins? to use & be seen with. SlipsStream Fins are supplied with Unique Spring Heel Straps made of Stainless Steel with a Highly Flexible Protective Outer Lining providing unparalleled comfort and ease of donning. 2 Flow Channels are incorporated into the blade to increase propulsion in the Water. The low weight further increases power and comfort, allowing the Diver to maintain optimal positioning. Available in 4 Sizes, Size Medium to suit UK Shoe Size up to 4 1/2, European Size up to 37, Foot Pocket Measures 7inches -18cm in length, 3 1/12 inches ? 8.9cm wide & 2 ? inches ? 7cm deep. Weight per pair = 2.3 Kgs.